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Themis J Michailides - One of the best experts on this subject based on the ideXlab platform.

  • effects of single drop impactions and natural and simulated rains on the dispersal of Botryosphaeria dothidea conidia
    Phytopathology, 2004
    Co-Authors: Neph Ahimera, David P Morgan, Simon Gisler, Themis J Michailides
    Abstract:

    ABSTRACT Laboratory and field experiments were conducted to study the dispersal of Botryosphaeria dothidea conidia using single-drop impactions and natural and simulated precipitations. For laboratory studies, 200 single drops were released from a height of 1 m on infected pistachio nuts. On pieces of photographic film, 50% of the droplets were collected within 20 mm (average droplet travel distance) of the target area, and the droplets ranged from 0.041 to 3.19 mm in diameter, with an average of 0.3 mm. Each droplet carried an average of 23 B. dothidea conidia. In 3 years of field experiments, rainwater was collected in funnels connected to bottles positioned at different heights inside the tree canopy and at different distances away from the edge of tree canopy in three commercial pistachio orchards in San Joaquin, Yolo, and Glenn counties in California. Numbers of conidia in rainwater varied among and within sampling seasons by sampling dates and orchards. Up to 67,000 conidia/ml were obtained in rainw...

  • spatiotemporal changes in the population structure of Botryosphaeria dothidea from california pistachio orchards
    Phytopathology, 2004
    Co-Authors: Themis J Michailides
    Abstract:

    Spatiotemporal changes in the population structure of Botryosphaeria dothidea, causal agent of panicle and shoot blight of pistachio, were analyzed by using microsatellite-primed polymerase chain reaction (MP-PCR), partial sequences of the RNA polymerase II (RPB2) gene, and vegetative compatibility groups (VCGs). We examined 390 isolates, 378 recovered from pistachio in seven counties of California from 1990 to 2001 and 12 recovered from peach, apple, and sycamore in Georgia, North Carolina, South Carolina, Illinois, and Pennsylvania. Six microsatellite primers generated 116 polymorphic bands. Based on MP-PCR data, we observed very high (>98%) levels of genetic identity among populations of B. dothidea collected from the commercial pistachio orchards in California. The near identity of these populations was supported by VCGs and partial sequences of the RBP2 gene. These findings suggest that populations of B. dothidea from commercial pistachio orchards are spatially and temporally stable, at least in the past 5 years.

  • relationships among propagule numbers of Botryosphaeria dothidea latent infections and severity of panicle and shoot blight in pistachio orchards
    Plant Disease, 2003
    Co-Authors: N Ahimera, G F Driever, Themis J Michailides
    Abstract:

    ABSTRACT Experiments were conducted between 1999 and 2001 to monitor the presence of propagules of Botryosphaeria dothidea and frequencies of latent infections on pistachio leaves and fruit clusters and to determine their relationships to panicle and shoot blight severity in commercial orchards. Numbers of B. dothidea propagules recovered from washing leaves and fruit clusters varied among the growing seasons and sampling dates. Lower numbers of B. dothidea propagules were obtained in 1999 and 2001 than in 2000. For the orchard in Glenn County, up to 75 propagules per leaf and 21 propagules per fruit cluster were recorded in 1999, compared with 365 and 248 propagules per leaf and fruit cluster, respectively, in 2000. Although more propagules were detected per leaf, the infection levels were higher on fruit clusters, suggesting that pistachio fruit is more susceptible to B. dothidea infection than leaves. Latent infections were detected as soon as leaves or fruit clusters started to expand and more infecti...

  • Antagonism of Paenibacillus lentimorbus to Botryosphaeria dothidea and Biological Control of Panicle and Shoot Blight of Pistachio.
    Plant Disease, 2003
    Co-Authors: Wei-qun Chen, Dan Felts, David P Morgan, Themis J Michailides
    Abstract:

    ABSTRACT A potential microbial fungicide, Paenibacillus lentimorbus isolate CBCA-2, against Botryosphaeria dothidea, the pistachio panicle and shoot blight fungus, was obtained from healthy pistachio leaves by both in vitro and in vivo screening techniques. CBCA-2 caused 100% inhibition of pycnidiospore germination after 24 h incubation at 25°C. Malformation of pycnidiospores and hyphae, and lysis and swollen pycnidiospores of B. dothidea occurred in the presence of cell suspensions of CBCA-2. Among the five media tested, nutrient yeast dextrose broth significantly increased the production of antifungal compounds. Application of culture filtrates of CBCA-2 suppressed disease on detached pistachio leaves, but washed bacterial cells did not inhibit lesion development. Development of lesions on excised dormant stems was inhibited only when the culture filtrate was applied before fungal inoculation. Survival of the CBCA-2 after treatment with azoxystrobin (Abound), benomyl (Benlate), tebuconazole (Elite), pro...

  • sensitivity of Botryosphaeria dothidea from california pistachio to tebuconazole
    Crop Protection, 2002
    Co-Authors: David P Morgan, Dan Felts, Themis J Michailides
    Abstract:

    Abstract Botryosphaeria blight of pistachio, caused by Botryosphaeria dothidea, is a devastating disease in California. Baseline sensitivity of B. dothidea to tebuconazole (Elite®) was determined using 105 wild-type single-spore isolates collected in 1999 and 2000 from a commercial pistachio orchard without a previous history of fungicide exposure in Glenn County, California. The 50% effective concentration (EC50) values of tebuconazole for these 105 isolates ranged from 0.019 to 0.159 μg/ml, and the mean EC50 was 0.080 μg/ml. In 2000, 277 single-spore isolates were collected from a fungicide trial orchard with 4 years of multi-sprays of tebuconazole in Glenn County, California. The EC50 values of these 277 isolates ranged from 0.037 to 0.291 μg/ml. The mean EC50 (0.099 μg/ml) of these 277 isolates was significantly higher (F=62.2, P

Guoping Wang - One of the best experts on this subject based on the ideXlab platform.

  • molecular characterization of a novel mycovirus infecting the phytopathogenic fungus Botryosphaeria dothidea
    Archives of Virology, 2020
    Co-Authors: Mengmeng Yang, Lifeng Zhai, Ni Hong, Feng Xiao, Xiaoqi Zhou, Guoping Wang
    Abstract:

    In this study, we report the molecular characterization of a novel positive-sense single-stranded RNA (+ssRNA) mycovirus from Botryosphaeria dothidea strain G91, which we name "Botryosphaeria dothidea botourmiavirus 1" (BdBOV-1). The complete genome of BdBOV-1 is 2547 nucleotides (nt) long, contains one open reading frame (ORF) potentially encoding an RNA-dependent RNA polymerase (RdRp), and shows a close relationship to mycoviruses of the family Botourmiaviridae. Phylogenetic analysis based on the RdRp sequences confirmed that BdBOV-1 clustered together with the members of the family Botourmiaviridae. To the best of our knowledge, this is the first report of a +ssRNA mycovirus infecting B. dothidea.

  • Comprehensive analysis of full genome sequence and Bd -milRNA/target mRNAs to discover the mechanism of hypovirulence in Botryosphaeria dothidea strains on pear infection with BdCV1 and BdPV1
    IMA fungus, 2019
    Co-Authors: Wangcheng Hu, Ni Hong, Guoping Wang, Yuekun Yang, Qiong Wang, Aiming Wang, Liping Wang
    Abstract:

    Pear ring rot disease, mainly caused by Botryosphaeria dothidea, is widespread in most pear and apple-growing regions. Mycoviruses are used for biocontrol, especially in fruit tree disease. BdCV1 (Botryosphaeria dothidea chrysovirus 1) and BdPV1 (Botryosphaeria dothidea partitivirus 1) influence the biological characteristics of B. dothidea strains. BdCV1 is a potential candidate for the control of fungal disease. Therefore, it is vital to explore interactions between B. dothidea and mycovirus to clarify the pathogenic mechanisms of B. dothidea and hypovirulence of B. dothidea in pear. A high-quality full-length genome sequence of the B. dothidea LW-Hubei isolate was obtained using Single Molecule Real-Time sequencing. It has high repeat sequence with 9.3% and DNA methylation existence in the genome. The 46.34 Mb genomes contained 14,091 predicted genes, which of 13,135 were annotated. B. dothidea was predicted to express 3833 secreted proteins. In bioinformatics analysis, 351 CAZy members, 552 transporters, 128 kinases, and 1096 proteins associated with plant-host interaction (PHI) were identified. RNA-silencing components including two endoribonuclease Dicer, four argonaute (Ago) and three RNA-dependent RNA polymerase (RdRp) molecules were identified and expressed in response to mycovirus infection. Horizontal transfer of the LW-C and LW-P strains indicated that BdCV1 induced host gene silencing in LW-C to suppress BdPV1 transmission. To investigate the role of RNA-silencing in B. dothidea defense, we constructed four small RNA libraries and sequenced B. dothidea micro-like RNAs (Bd-milRNAs) produced in response to BdCV1 and BdPV1 infection. Among these, 167 conserved and 68 candidate novel Bd-milRNAs were identified, of which 161 conserved and 20 novel Bd-milRNA were differentially expressed. WEGO analysis revealed involvement of the differentially expressed Bd-milRNA-targeted genes in metabolic process, catalytic activity, cell process and response to stress or stimulus. BdCV1 had a greater effect on the phenotype, virulence, conidiomata, vertical and horizontal transmission ability, and mycelia cellular structure biological characteristics of B. dothidea strains than BdPV1 and virus-free strains. The results obtained in this study indicate that mycovirus regulates biological processes in B. dothidea through the combined interaction of antiviral defense mediated by RNA-silencing and milRNA-mediated regulation of target gene mRNA expression.

  • characterization of a novel victorivirus isolated from the phytopathogenic fungus Botryosphaeria dothidea
    Archives of Virology, 2019
    Co-Authors: Mengmeng Yang, Lifeng Zhai, Ni Hong, Min Fu, Feng Xiao, Guoping Wang
    Abstract:

    Botryosphaeria dothidea is an important pathogenic fungus that causes serious diseases in fruits and trunks of many wood plant species worldwide. In this study, 28 B. dothidea strains isolated from pear trunk samples showing stem wart or canker symptoms were used to detect double-stranded RNA (dsRNA) viruses. The dsRNA bands with the size of ~ 1.0 to ~ 6.0 kbp were examined from ten strains. Here, we reported a novel dsRNA mycovirus, tentatively named as Botryosphaeria dothidea victorivirus 2 (BdVV2), isolated from the B. dothidea strain MSD53. BdVV2 contained spherical virions that were ~ 38 nm in diameter consisting of a single linear dsRNA genome of 5,090 bp in length. The BdVV2 genome contained two overlapping open reading frames (ORFs) encoding a putative coat protein (CP) and an RNA-dependent RNA polymerase (RdRp), which shared significant amino acid identities of 68% and 60% with the corresponding proteins of Sphaeropsis sapinea RNA viruses 1 (SsRV1). Phylogenetic analyses based on the aa sequences of CP and RdRp both showed that BdVV2 was phylogenetically related to the members of the genus Victorivirus in the family Totiviridae. BdVV2 is thus a novel victorivirus isolated from the phytopathogenic fungus B. dothidea.

  • characterization of a botybirnavirus conferring hypovirulence in the phytopathogenic fungus Botryosphaeria dothidea
    Viruses, 2019
    Co-Authors: Lifeng Zhai, Ni Hong, Meixin Zhang, Mengmeng Yang, Guoping Wang
    Abstract:

    A double-stranded RNA (dsRNA) virus was isolated and characterized from strain EW220 of the phytopathogenic fungus Botryosphaeria dothidea. The full-length cDNAs of the dsRNAs were 6434 bp and 5986 bp in size, respectively. The largest dsRNA encodes a cap-pol fusion protein that contains a coat protein gene and an RNA-dependent RNA polymerase (RdRp) domain, and the second dsRNA encodes a hypothetical protein. Genome sequence analysis revealed that the sequences of the dsRNA virus shared 99% identity with Bipolaris maydis botybirnavirus 1(BmBRV1) isolated from the causal agent of corn southern leaf blight, Bipolaris maydis. Hence, the dsRNA virus constitutes a new strain of BmBRV1 and was named Bipolaris maydis botybirnavirus 1 strain BdEW220 (BmBRV1-BdEW220). BmBRV1-BdEW220 contains spherical virions that are 37 nm in diameter and consist of two dsRNA segments. The structural proteins of the BmBRV1-BdEW220 virus particles were 110 kDa, 90 kDa, and 80 kDa and were encoded by dsRNA1 and 2-ORFs. Phylogenetic reconstruction indicated that BmBRV1 and BmBRV1-BdEW220 are phylogenetically related to the genus Botybirnavirus. Importantly, BmBRV1-BdEW220 influences the growth of B. dothidea and confers hypovirulence to the fungal host. To our knowledge, this is the first report of a botybirnavirus in B. dothidea.

  • Characterization of a Bbotybirnavirus Conferring Hypovirulence in the Pear Stem Wart Disease Phytopathogenic Fungus Botryosphaeria dothidea
    2019
    Co-Authors: Lifeng Zhai, Ni Hong, Mengmeng Yang, Meixing Zhang, Guoping Wang
    Abstract:

    A double-stranded RNA (dsRNA) virus was isolated and characterized from a strain EW220 of the phytopathogenic fungus Botryosphaeria dothidea. The full-length cDNAs of dsRNAs were 6,434 bp and 5,986 bp in size, respectively. The largest dsRNA of BdBRV1 encodes a cap-pol fusion protein that contains part coat protein gene and a RNA-dependent RNA polymerase (RdRp) domain, and the second dsRNA encodes a hypothetical protein. The dsRNA virus was named Botryosphaeria dothidea botybirnavirus 1 (BdBRV1). BdBRV1 contains spherical virions that are 37 nm in diameter consisting of two segments. The structural proteins of BdBRV1 virus particles were 110 kDa, 90 kDa, and 80 kDa, which encoded by dsRNA1 and 2-ORFs. The analysis of genome sequences revealed that the sequences of BdBRV1 shared 99% identity with Bipolaris maydis botybirnavirus 1(BmBRV1). Phylogenetic reconstruction indicated that BdBRV1 and BmBRV1 are phylogenetically related to the genus Botybirnavirus. Importantly, BdBRV1 influences the growth of B. dothidea and confers hypovirulence to the fungal host. BdBRV1 and BmBRV1 were two strains of the same virus. To our knowledge, this is the first report of a botybirnavirus in B. dothidea and our result might be the first funding in the different fungi infected by the same virus.

David P Morgan - One of the best experts on this subject based on the ideXlab platform.

  • effects of single drop impactions and natural and simulated rains on the dispersal of Botryosphaeria dothidea conidia
    Phytopathology, 2004
    Co-Authors: Neph Ahimera, David P Morgan, Simon Gisler, Themis J Michailides
    Abstract:

    ABSTRACT Laboratory and field experiments were conducted to study the dispersal of Botryosphaeria dothidea conidia using single-drop impactions and natural and simulated precipitations. For laboratory studies, 200 single drops were released from a height of 1 m on infected pistachio nuts. On pieces of photographic film, 50% of the droplets were collected within 20 mm (average droplet travel distance) of the target area, and the droplets ranged from 0.041 to 3.19 mm in diameter, with an average of 0.3 mm. Each droplet carried an average of 23 B. dothidea conidia. In 3 years of field experiments, rainwater was collected in funnels connected to bottles positioned at different heights inside the tree canopy and at different distances away from the edge of tree canopy in three commercial pistachio orchards in San Joaquin, Yolo, and Glenn counties in California. Numbers of conidia in rainwater varied among and within sampling seasons by sampling dates and orchards. Up to 67,000 conidia/ml were obtained in rainw...

  • Antagonism of Paenibacillus lentimorbus to Botryosphaeria dothidea and Biological Control of Panicle and Shoot Blight of Pistachio.
    Plant Disease, 2003
    Co-Authors: Wei-qun Chen, Dan Felts, David P Morgan, Themis J Michailides
    Abstract:

    ABSTRACT A potential microbial fungicide, Paenibacillus lentimorbus isolate CBCA-2, against Botryosphaeria dothidea, the pistachio panicle and shoot blight fungus, was obtained from healthy pistachio leaves by both in vitro and in vivo screening techniques. CBCA-2 caused 100% inhibition of pycnidiospore germination after 24 h incubation at 25°C. Malformation of pycnidiospores and hyphae, and lysis and swollen pycnidiospores of B. dothidea occurred in the presence of cell suspensions of CBCA-2. Among the five media tested, nutrient yeast dextrose broth significantly increased the production of antifungal compounds. Application of culture filtrates of CBCA-2 suppressed disease on detached pistachio leaves, but washed bacterial cells did not inhibit lesion development. Development of lesions on excised dormant stems was inhibited only when the culture filtrate was applied before fungal inoculation. Survival of the CBCA-2 after treatment with azoxystrobin (Abound), benomyl (Benlate), tebuconazole (Elite), pro...

  • sensitivity of Botryosphaeria dothidea from california pistachio to tebuconazole
    Crop Protection, 2002
    Co-Authors: David P Morgan, Dan Felts, Themis J Michailides
    Abstract:

    Abstract Botryosphaeria blight of pistachio, caused by Botryosphaeria dothidea, is a devastating disease in California. Baseline sensitivity of B. dothidea to tebuconazole (Elite®) was determined using 105 wild-type single-spore isolates collected in 1999 and 2000 from a commercial pistachio orchard without a previous history of fungicide exposure in Glenn County, California. The 50% effective concentration (EC50) values of tebuconazole for these 105 isolates ranged from 0.019 to 0.159 μg/ml, and the mean EC50 was 0.080 μg/ml. In 2000, 277 single-spore isolates were collected from a fungicide trial orchard with 4 years of multi-sprays of tebuconazole in Glenn County, California. The EC50 values of these 277 isolates ranged from 0.037 to 0.291 μg/ml. The mean EC50 (0.099 μg/ml) of these 277 isolates was significantly higher (F=62.2, P

  • dynamics and pattern of latent infection caused by Botryosphaeria dothidea on pistachio buds
    Plant Disease, 2002
    Co-Authors: N Ntahimpera, David P Morgan, G F Driever, D Felts, Themis J Michailides
    Abstract:

    ABSTRACT A study was conducted in four commercial pistachio orchards to monitor the presence and pattern of external contamination and latent infections of buds by Botryosphaeria dothidea between 1998 and 2000. Symptomless buds were sampled every 2 to 3 weeks and analyzed either by a washing/crushing method or by direct plating of split (half) or intact buds on lactic acid potato dextrose agar. The proportion of infected buds varied among orchards over time. Levels of latent infections were highest in February and March when they reached as much as 60% in orchards of Glenn and Yolo counties. This period corresponded to the months with the highest rainfall. Buds collected from orchards in Glenn and Yolo counties had, in general, higher incidence of infection than buds from San Joaquin and Merced counties. Buds became infected in June immediately after their formation. Infection incidence on basal segments of buds from male trees was approximately twice (19%) that of apical or middle segments (11%). Plating...

  • effects of water stress on Botryosphaeria blight of pistachio caused by Botryosphaeria dothidea
    Plant Disease, 2001
    Co-Authors: David P Morgan, Themis J Michailides
    Abstract:

    ABSTRACT The effects of water potential (Ψ) on spore germination, germ tube elongation, mycelial growth of Botryosphaeria dothidea, and development of Botryosphaeria blight of pistachio caused by this fungus were studied in the laboratory and greenhouse. In laboratory tests, spore germination, germ tube elongation, and mycelial growth of B. dothidea increased as Ψ decreased from 0 to -2.0 MPa and declined as Ψ decreased below -2.0 MPa. Water stress (Ψ -0.485 MPa) in both 1999 and 2000 experiments. In a similar experiment using 1-year-old potted pistachio trees in 2000, withholding water treatments did not cause enough drought stress in pistachio leaves (Ψ > -0.584 MPa) and did not result in higher disease than the nonstress...

Lifeng Zhai - One of the best experts on this subject based on the ideXlab platform.

  • molecular characterization of a novel mycovirus infecting the phytopathogenic fungus Botryosphaeria dothidea
    Archives of Virology, 2020
    Co-Authors: Mengmeng Yang, Lifeng Zhai, Ni Hong, Feng Xiao, Xiaoqi Zhou, Guoping Wang
    Abstract:

    In this study, we report the molecular characterization of a novel positive-sense single-stranded RNA (+ssRNA) mycovirus from Botryosphaeria dothidea strain G91, which we name "Botryosphaeria dothidea botourmiavirus 1" (BdBOV-1). The complete genome of BdBOV-1 is 2547 nucleotides (nt) long, contains one open reading frame (ORF) potentially encoding an RNA-dependent RNA polymerase (RdRp), and shows a close relationship to mycoviruses of the family Botourmiaviridae. Phylogenetic analysis based on the RdRp sequences confirmed that BdBOV-1 clustered together with the members of the family Botourmiaviridae. To the best of our knowledge, this is the first report of a +ssRNA mycovirus infecting B. dothidea.

  • characterization of a novel victorivirus isolated from the phytopathogenic fungus Botryosphaeria dothidea
    Archives of Virology, 2019
    Co-Authors: Mengmeng Yang, Lifeng Zhai, Ni Hong, Min Fu, Feng Xiao, Guoping Wang
    Abstract:

    Botryosphaeria dothidea is an important pathogenic fungus that causes serious diseases in fruits and trunks of many wood plant species worldwide. In this study, 28 B. dothidea strains isolated from pear trunk samples showing stem wart or canker symptoms were used to detect double-stranded RNA (dsRNA) viruses. The dsRNA bands with the size of ~ 1.0 to ~ 6.0 kbp were examined from ten strains. Here, we reported a novel dsRNA mycovirus, tentatively named as Botryosphaeria dothidea victorivirus 2 (BdVV2), isolated from the B. dothidea strain MSD53. BdVV2 contained spherical virions that were ~ 38 nm in diameter consisting of a single linear dsRNA genome of 5,090 bp in length. The BdVV2 genome contained two overlapping open reading frames (ORFs) encoding a putative coat protein (CP) and an RNA-dependent RNA polymerase (RdRp), which shared significant amino acid identities of 68% and 60% with the corresponding proteins of Sphaeropsis sapinea RNA viruses 1 (SsRV1). Phylogenetic analyses based on the aa sequences of CP and RdRp both showed that BdVV2 was phylogenetically related to the members of the genus Victorivirus in the family Totiviridae. BdVV2 is thus a novel victorivirus isolated from the phytopathogenic fungus B. dothidea.

  • characterization of a botybirnavirus conferring hypovirulence in the phytopathogenic fungus Botryosphaeria dothidea
    Viruses, 2019
    Co-Authors: Lifeng Zhai, Ni Hong, Meixin Zhang, Mengmeng Yang, Guoping Wang
    Abstract:

    A double-stranded RNA (dsRNA) virus was isolated and characterized from strain EW220 of the phytopathogenic fungus Botryosphaeria dothidea. The full-length cDNAs of the dsRNAs were 6434 bp and 5986 bp in size, respectively. The largest dsRNA encodes a cap-pol fusion protein that contains a coat protein gene and an RNA-dependent RNA polymerase (RdRp) domain, and the second dsRNA encodes a hypothetical protein. Genome sequence analysis revealed that the sequences of the dsRNA virus shared 99% identity with Bipolaris maydis botybirnavirus 1(BmBRV1) isolated from the causal agent of corn southern leaf blight, Bipolaris maydis. Hence, the dsRNA virus constitutes a new strain of BmBRV1 and was named Bipolaris maydis botybirnavirus 1 strain BdEW220 (BmBRV1-BdEW220). BmBRV1-BdEW220 contains spherical virions that are 37 nm in diameter and consist of two dsRNA segments. The structural proteins of the BmBRV1-BdEW220 virus particles were 110 kDa, 90 kDa, and 80 kDa and were encoded by dsRNA1 and 2-ORFs. Phylogenetic reconstruction indicated that BmBRV1 and BmBRV1-BdEW220 are phylogenetically related to the genus Botybirnavirus. Importantly, BmBRV1-BdEW220 influences the growth of B. dothidea and confers hypovirulence to the fungal host. To our knowledge, this is the first report of a botybirnavirus in B. dothidea.

  • Characterization of a Bbotybirnavirus Conferring Hypovirulence in the Pear Stem Wart Disease Phytopathogenic Fungus Botryosphaeria dothidea
    2019
    Co-Authors: Lifeng Zhai, Ni Hong, Mengmeng Yang, Meixing Zhang, Guoping Wang
    Abstract:

    A double-stranded RNA (dsRNA) virus was isolated and characterized from a strain EW220 of the phytopathogenic fungus Botryosphaeria dothidea. The full-length cDNAs of dsRNAs were 6,434 bp and 5,986 bp in size, respectively. The largest dsRNA of BdBRV1 encodes a cap-pol fusion protein that contains part coat protein gene and a RNA-dependent RNA polymerase (RdRp) domain, and the second dsRNA encodes a hypothetical protein. The dsRNA virus was named Botryosphaeria dothidea botybirnavirus 1 (BdBRV1). BdBRV1 contains spherical virions that are 37 nm in diameter consisting of two segments. The structural proteins of BdBRV1 virus particles were 110 kDa, 90 kDa, and 80 kDa, which encoded by dsRNA1 and 2-ORFs. The analysis of genome sequences revealed that the sequences of BdBRV1 shared 99% identity with Bipolaris maydis botybirnavirus 1(BmBRV1). Phylogenetic reconstruction indicated that BdBRV1 and BmBRV1 are phylogenetically related to the genus Botybirnavirus. Importantly, BdBRV1 influences the growth of B. dothidea and confers hypovirulence to the fungal host. BdBRV1 and BmBRV1 were two strains of the same virus. To our knowledge, this is the first report of a botybirnavirus in B. dothidea and our result might be the first funding in the different fungi infected by the same virus.

  • characterization of a novel double stranded rna mycovirus conferring hypovirulence from the phytopathogenic fungus Botryosphaeria dothidea
    Virology, 2016
    Co-Authors: Lifeng Zhai, Ni Hong, Meixin Zhang, Min Fu, Jun Xiang, Zuokun Yang, Guoping Wang
    Abstract:

    A novel double-stranded RNA (dsRNA) virus, designated as Botryosphaeria dothidea RNA virus 1 (BdRV1), isolated from a hypovirulent strain YZN115 of Botryosphaeria dothidea was biologically and molecularly characterized. The genome of BdRV1 comprises of five dsRNAs. Each dsRNA contains a single open reading frame. The proteins encoded by dsRNA1-4 shared significant amino acid identities of 55%, 47%, 43% and 53% with the corresponding proteins of Aspergillus fumigatus tetramycovirus-1. DsRNA1, 3, and 4 of BdRV1 encoded an RNA-dependent RNA polymerase, a viral methyltransferase, and a P-A-S-rich protein, respectively. Function of proteins encoded by the dsRNA2 and dsRNA5 were unknown. BdRV1 conferred hypovirulence for its host and could be transmitted through conidia and hyphae contact.

Ni Hong - One of the best experts on this subject based on the ideXlab platform.

  • molecular characterization of a novel mycovirus infecting the phytopathogenic fungus Botryosphaeria dothidea
    Archives of Virology, 2020
    Co-Authors: Mengmeng Yang, Lifeng Zhai, Ni Hong, Feng Xiao, Xiaoqi Zhou, Guoping Wang
    Abstract:

    In this study, we report the molecular characterization of a novel positive-sense single-stranded RNA (+ssRNA) mycovirus from Botryosphaeria dothidea strain G91, which we name "Botryosphaeria dothidea botourmiavirus 1" (BdBOV-1). The complete genome of BdBOV-1 is 2547 nucleotides (nt) long, contains one open reading frame (ORF) potentially encoding an RNA-dependent RNA polymerase (RdRp), and shows a close relationship to mycoviruses of the family Botourmiaviridae. Phylogenetic analysis based on the RdRp sequences confirmed that BdBOV-1 clustered together with the members of the family Botourmiaviridae. To the best of our knowledge, this is the first report of a +ssRNA mycovirus infecting B. dothidea.

  • Comprehensive analysis of full genome sequence and Bd -milRNA/target mRNAs to discover the mechanism of hypovirulence in Botryosphaeria dothidea strains on pear infection with BdCV1 and BdPV1
    IMA fungus, 2019
    Co-Authors: Wangcheng Hu, Ni Hong, Guoping Wang, Yuekun Yang, Qiong Wang, Aiming Wang, Liping Wang
    Abstract:

    Pear ring rot disease, mainly caused by Botryosphaeria dothidea, is widespread in most pear and apple-growing regions. Mycoviruses are used for biocontrol, especially in fruit tree disease. BdCV1 (Botryosphaeria dothidea chrysovirus 1) and BdPV1 (Botryosphaeria dothidea partitivirus 1) influence the biological characteristics of B. dothidea strains. BdCV1 is a potential candidate for the control of fungal disease. Therefore, it is vital to explore interactions between B. dothidea and mycovirus to clarify the pathogenic mechanisms of B. dothidea and hypovirulence of B. dothidea in pear. A high-quality full-length genome sequence of the B. dothidea LW-Hubei isolate was obtained using Single Molecule Real-Time sequencing. It has high repeat sequence with 9.3% and DNA methylation existence in the genome. The 46.34 Mb genomes contained 14,091 predicted genes, which of 13,135 were annotated. B. dothidea was predicted to express 3833 secreted proteins. In bioinformatics analysis, 351 CAZy members, 552 transporters, 128 kinases, and 1096 proteins associated with plant-host interaction (PHI) were identified. RNA-silencing components including two endoribonuclease Dicer, four argonaute (Ago) and three RNA-dependent RNA polymerase (RdRp) molecules were identified and expressed in response to mycovirus infection. Horizontal transfer of the LW-C and LW-P strains indicated that BdCV1 induced host gene silencing in LW-C to suppress BdPV1 transmission. To investigate the role of RNA-silencing in B. dothidea defense, we constructed four small RNA libraries and sequenced B. dothidea micro-like RNAs (Bd-milRNAs) produced in response to BdCV1 and BdPV1 infection. Among these, 167 conserved and 68 candidate novel Bd-milRNAs were identified, of which 161 conserved and 20 novel Bd-milRNA were differentially expressed. WEGO analysis revealed involvement of the differentially expressed Bd-milRNA-targeted genes in metabolic process, catalytic activity, cell process and response to stress or stimulus. BdCV1 had a greater effect on the phenotype, virulence, conidiomata, vertical and horizontal transmission ability, and mycelia cellular structure biological characteristics of B. dothidea strains than BdPV1 and virus-free strains. The results obtained in this study indicate that mycovirus regulates biological processes in B. dothidea through the combined interaction of antiviral defense mediated by RNA-silencing and milRNA-mediated regulation of target gene mRNA expression.

  • characterization of a novel victorivirus isolated from the phytopathogenic fungus Botryosphaeria dothidea
    Archives of Virology, 2019
    Co-Authors: Mengmeng Yang, Lifeng Zhai, Ni Hong, Min Fu, Feng Xiao, Guoping Wang
    Abstract:

    Botryosphaeria dothidea is an important pathogenic fungus that causes serious diseases in fruits and trunks of many wood plant species worldwide. In this study, 28 B. dothidea strains isolated from pear trunk samples showing stem wart or canker symptoms were used to detect double-stranded RNA (dsRNA) viruses. The dsRNA bands with the size of ~ 1.0 to ~ 6.0 kbp were examined from ten strains. Here, we reported a novel dsRNA mycovirus, tentatively named as Botryosphaeria dothidea victorivirus 2 (BdVV2), isolated from the B. dothidea strain MSD53. BdVV2 contained spherical virions that were ~ 38 nm in diameter consisting of a single linear dsRNA genome of 5,090 bp in length. The BdVV2 genome contained two overlapping open reading frames (ORFs) encoding a putative coat protein (CP) and an RNA-dependent RNA polymerase (RdRp), which shared significant amino acid identities of 68% and 60% with the corresponding proteins of Sphaeropsis sapinea RNA viruses 1 (SsRV1). Phylogenetic analyses based on the aa sequences of CP and RdRp both showed that BdVV2 was phylogenetically related to the members of the genus Victorivirus in the family Totiviridae. BdVV2 is thus a novel victorivirus isolated from the phytopathogenic fungus B. dothidea.

  • characterization of a botybirnavirus conferring hypovirulence in the phytopathogenic fungus Botryosphaeria dothidea
    Viruses, 2019
    Co-Authors: Lifeng Zhai, Ni Hong, Meixin Zhang, Mengmeng Yang, Guoping Wang
    Abstract:

    A double-stranded RNA (dsRNA) virus was isolated and characterized from strain EW220 of the phytopathogenic fungus Botryosphaeria dothidea. The full-length cDNAs of the dsRNAs were 6434 bp and 5986 bp in size, respectively. The largest dsRNA encodes a cap-pol fusion protein that contains a coat protein gene and an RNA-dependent RNA polymerase (RdRp) domain, and the second dsRNA encodes a hypothetical protein. Genome sequence analysis revealed that the sequences of the dsRNA virus shared 99% identity with Bipolaris maydis botybirnavirus 1(BmBRV1) isolated from the causal agent of corn southern leaf blight, Bipolaris maydis. Hence, the dsRNA virus constitutes a new strain of BmBRV1 and was named Bipolaris maydis botybirnavirus 1 strain BdEW220 (BmBRV1-BdEW220). BmBRV1-BdEW220 contains spherical virions that are 37 nm in diameter and consist of two dsRNA segments. The structural proteins of the BmBRV1-BdEW220 virus particles were 110 kDa, 90 kDa, and 80 kDa and were encoded by dsRNA1 and 2-ORFs. Phylogenetic reconstruction indicated that BmBRV1 and BmBRV1-BdEW220 are phylogenetically related to the genus Botybirnavirus. Importantly, BmBRV1-BdEW220 influences the growth of B. dothidea and confers hypovirulence to the fungal host. To our knowledge, this is the first report of a botybirnavirus in B. dothidea.

  • Characterization of a Bbotybirnavirus Conferring Hypovirulence in the Pear Stem Wart Disease Phytopathogenic Fungus Botryosphaeria dothidea
    2019
    Co-Authors: Lifeng Zhai, Ni Hong, Mengmeng Yang, Meixing Zhang, Guoping Wang
    Abstract:

    A double-stranded RNA (dsRNA) virus was isolated and characterized from a strain EW220 of the phytopathogenic fungus Botryosphaeria dothidea. The full-length cDNAs of dsRNAs were 6,434 bp and 5,986 bp in size, respectively. The largest dsRNA of BdBRV1 encodes a cap-pol fusion protein that contains part coat protein gene and a RNA-dependent RNA polymerase (RdRp) domain, and the second dsRNA encodes a hypothetical protein. The dsRNA virus was named Botryosphaeria dothidea botybirnavirus 1 (BdBRV1). BdBRV1 contains spherical virions that are 37 nm in diameter consisting of two segments. The structural proteins of BdBRV1 virus particles were 110 kDa, 90 kDa, and 80 kDa, which encoded by dsRNA1 and 2-ORFs. The analysis of genome sequences revealed that the sequences of BdBRV1 shared 99% identity with Bipolaris maydis botybirnavirus 1(BmBRV1). Phylogenetic reconstruction indicated that BdBRV1 and BmBRV1 are phylogenetically related to the genus Botybirnavirus. Importantly, BdBRV1 influences the growth of B. dothidea and confers hypovirulence to the fungal host. BdBRV1 and BmBRV1 were two strains of the same virus. To our knowledge, this is the first report of a botybirnavirus in B. dothidea and our result might be the first funding in the different fungi infected by the same virus.